I compiled this game on OS X 10.9.5 and Ubuntu 14.04, and it works, but I do not know how to activate a fullscreen mode in AVP. I tried to use a shortcut ALT-ENTER, but it does not work on both operating systems. Can you help me?

Thank you for confirming – I couldn’t get fullscreen switching to work either, but wasn’t sure if it was just me as it used to work long ago. Working fullscreen toggling might end up being a SDL2 version-only feature at this point; I’ll have to see how easy it is to do. In the meantime, add -f to the command line when running avp, as that will make the game start in fullscreen mode.